Electric switch



April 25, 1939.

P. J O'BRIEN ELECTRIC SWITCH e Sheets-Sheet 1 Filed April 9, 1938 April 25, 1939. P. J. O'BRIEN ELECTRIC SWITCH Filed April 9, 1938 6 Sheets-Sheet 2 I um I "II.

5 &c"; nay

Mick J: 015

I Inn 4 Z w w y w April 25, 1939 P. .1. OBRIEN a ELECTRIC SWITCH 6 Sheets- Sheet 3 Filed April 9, 1938 April 25,1939. P, J, BRIEN 1 2,156,024

ELECTRIC SWITCH v Filed April 9, l958 6 Sheets-Sheet 4 April 25, 19391 P. J. O BRIEN ELECTRIC SWITCH Filed April 9, 1958 6 Sheets-Sheet 5 P. J. O'BRIEN ELECTRIC SWITCH April 25, 1939.

6 Sheets-Sheet 6 Filed April 9, 19 58 Ewell-$1 Patented Apr. 25, 1939 UNITED STATES @FFICE 11 Claims.

This invention relates to electrical switches, and more particularly to switches of the type wherein the switch blade is clamped'to the contacts with which itis associated when in its g operative position.

An important object of the present invention is the provision in a construction 01' this character of an arrangementwhereby. a clamp-operating mechanism associated with the switch serves at to the same time as a portion of the switch-bladeoperating mechanism and is positively locked against movement into or out of clamping position until the switch blade has first been moved to its operative or contact-engaging position.

A further object of the invention is the provision in a construction 01 this character of a simple link and lever arrangement which, without the aid of external latches or the like, serves to hold the clamp-operating elements against operation except when the switch is in its contact-engaging position.

A further object of the invention is the provision of a structure of this character which is readily adaptable toeither stick or group operation.

These and other objects I attain by the construction shown in the accompanying drawings wherein, for the purpose oi. illustration, I have shown a preferred embodiment oi my invention and wherein:

Fig. 1 is a longitudinal sectional view through one form of switch embodying my invention;

Fig. 2 is a plan view thereof;

Fig. 3 is a section on line 3-8 of Fig. 1;

85 Fig. 4 is a detail view showing the position of thecontrol mechanism after the clamps have been released;

Fig. 5 is a plan view of the mechanism when in the position shown in Fig. 4;

40 Fig. 6 is a sectional view showing positions of the parts when the switch is in its opened position;

Fig. 7 is a detail view showing the adjustment of the clamping elements;

45 Fig. 8 is a side elevation of a second form of switch embodying my invention, the switch being shown in closed position;

Fig. 9 is a plan view of the switch of Fig. 8;

Fig. 10 is an end elevation thereof;

50 Fig. 11 is a detail view showing the clamp adjustment in this form of switch; a

Fig. 12 is a detail side elevation showing the position of the parts when the clamps are released; v

55 Fig. 13 is a similar view showing the position (Cl. zoo-roe) oi the parts when the switch is in its open position;

Fig. 1% is a longitudinal sectional view through a further switch embodying my invention;

Fig. 15 is a section on line l5-l5 of Fig.'14; 5

Fig. 16 is a section on line it-it of Fig. 14; and

Fig. 17 is a detail view partially in section showing the switch of Fig. 14 in the open position. 10

Referring now to the drawings, and more particularly to that form oi the invention shown in Figures 1 to 7, the numeral I8 generally indicates insulators bearing stationary contacts II and Ma. equipped with the usual bus connections l5 l2, 02a. A blade generally designated at [3 .is pivoted to the contact ii for rotation about an axis M. In the present;instance the stationary contacts ii and i la. are each shown as comprising a pair of upstanding conductors, those of the Q contact it being apertured for the passage of the pivots it, while those of the contact I la have notches it opening through their upper ends to permit introduction of clamping pins 11. The pivot pins l5 and clamping pins 11 each comprise 25 a head it having a small locking pin is adapted to selectively engage in any of a series of openings 20 formed in the adjacent member of the blade 13, a shank 2i passing through the associated contact element and both associated members l3a, I3b forming the adjacent side of the blade and a threaded inner end 22 adapted for engagement with a nut element 23 presently to be described. The inner ends of the elements l5 and H at opposite sides of the switch are oppositely threaded. While the members I 5 have been referred to as pivot pins, they act not only in this capacity but as clamping pins, as will hereinafter become obvious.

Pivotally connected to the base 24 of contact H at 25 is a link 26, and pivotally connected to the opposite sides of the blade element by pivots 21 which substantially align with the pivots 25 when-the blade 13 is in its closed position illustrated in Fig. 1, are levers 28 the opposite ends of which are pivotally connected to the link 26 at 29. Pivots 29 are axially spaced through a distance equal to the axial spacing between the pivotal axis ll of the blade and the pivots 25. The adjacent inner ends 22 of the clamping pivots l5 and. clamping studs I1 are engaged by'the double nut elements 30, '30a'embodying nuts 23, these double nut elements having radial arms 3|,- 3la. The arm 3| of nut 30 is connected through alink 32 with anans'ulfl-rarm33 uponone of F the outer end of the arm 3|.

' against switchmovement, these links must first.

Assuming the parts to be in the position illustrated in Fig. 1, at which time the double nut elements and their associated clamping members |5 or I! have clamped the blade elements l3a, l3b at the respective sides of the switch blade upon the associated stationary contacts, if

pressure be applied to the arm 3| a in an attempt to open the switch, the switch is held in its locked position until the parts have moved to the position shown in Fig. 4. This is due to the fact that in order for the switch blade to move the links 26, which, in the position of Fig. 1, have their pivots 28 out of alignment with the pivot l4 of the switch forming a positive lock be moved to bring pivots 28 and I4 into alignment. Accordingly, the only movement which can be imparted to the switch structure at this time through pressure applied to arm 3|a is a rotation of this arm, which rotation, through link 35, is imparted to arm 3| and through link 32 to the linl; assembly 26, 28, oscillating this assembly about the pivots 25, 21 until the pivot 28 aligns axially with the pivots I5. This rotation imparts a simultaneous rotation to the double nut assemblies 38, 38a releasing the clamping action of the clamps, following which the switch.

blade may rotate about its pivot to the position shown in Fig. 6. Due to the connection between links 28 and the arm 3| through link 32, and to the fact that this closing pressure is applied to the links 28 between the ends thereof, these links must rotate about their pivot 28 until the pivots 21 again align with the pivots 25. At this til 1c the blade will be in its closed position and properly engage with its contacts, and further pressure applied will cause the double nut assemblies 38, 38a to rotate about their pivots and again clamp the same in position.

In the form of invention shown in Figs. 8 to 13, the stationary contacts 36 and 3641 are unitary elements but otherwise correspond directly to the stationary contacts hereinbefore described. The blade 31 consists of a pair of spaced elements 31a, 31b adapted for engagementwithopposite sides of the contact and but two clamping elements 38 and 38a are utilized. These clamping elements are identical in structure, each comprising a headed stud 39 having a lockable rotatable adjustment generally designated at 48, a shank 4| passing through both blades of the switch, and a threaded end 42' engaged by a single nut assembly 43. These nut assemblies are identical with the exception of the fact that that associated with the member 38a has an arm 44 for engagement with an operating member, each nut assembly having, a pivot 45 for engagement with the end ofa connecting link 46. Adjacent contact 36 and supported in the base thereof is a bracket 41 having a pivot 48 to which is connected one end of a link 48. Link 48, in turn, engages a pivot 58 the axis of which is spaced from the axis of pivot 48 a distance equal to the spacing of thisaxis from the axis of the switch axis 5| of the clamping blade pivot 38.

Secured to link 46 is an arm 52 the inner end of which bears pivot 58. Pivot 58 being afllxed to the link 46, in common with the pivotal connection 45, must move through an are parallel to the pivot 45 and it, accordingly, follows that the distance between centers of pivots 48 and 58 must be exactly the same as that between pivotal axis 5| and that of the associated pivot 45.

' In this case the operation is substantially identical with that previously described. When pressure is applied to the arm 44 in an attempt to open the switch, the link 49 serves as a lock until link 46 has been moved longitudinally to bring the axis of pivot 58 into alignment with the pivotal axis 5|. At this time, as seen in Fig. 12, the axis of pivot 45 is in approximate linear align ent with the axes of pivots 5| and 48. It

will be seen that any further movement of pivot 45 abcut the pivot 5| as an axis must be as a result of turning movement of the blade 31 aboutthe same pivot, for otherwise the pivot 45 would have to approach the pivot 58. Accordingly, during subsequent movement the pivot 58 remains in alignment with the pivot 5|, the parts finally assuming the position shown in-Fig. 13.

In return movement from the position of Fig. 13, if any longitudinal strain is placed on link 46 as will result in an; attempt to close the switch, pivot 45. can only move from its final position while the pivot 58 remains in alignment with pivot 5|, for obviously any movement of link 46 which is unaccompanied by a movement of the switch blade 4| will bring about the same circumstances, i. e., a recession of pivot 58 from pivot 48, which is prevented by link 48. The switch blade, therefore, moves to its closed position' before there is any possible effective movement of the nut 43 with relation to the threaded portion 42 upon which it is mounted. After the blade is fully closed, longitudinal movement of link 46 is permitted and the clamps may thus be thrown into operation. In this form of the invention I preferably provide the link 48 and bracket 41with coacting stop elements 48a, 41a which iengage and check the movement of the link in; the position shown in Fig. 12.

In the form shown in Figs. 14 to 17, stationary contacts 53, 53a comprise spaced members 54 between which the switch blade ,55 is adapted to be disposed. The switch blade comprisesvspaced side elements 56 pivoted to the contact 53 at 51. These contact elements are connected intermediate their ends'by a pair of spacing elements 58 each embodyinga bearing 58 for a shaft 68. The ends of shaft 68 are connected by toggle links 6| to the side elements 56 of the blades, these toggle links being disposed in substantial alignment when the blade is in its closed position with the opposed elements constituting the stationary contacts 53 and 53a so that when the toggle links are properly actuated the blade elements 56 will move outwardly for forcible clamping engagement with the stationary contacts. Shaft 68 has an arm 62 connected thereto, the purpose of which will presently appear.

Pivoted to the base 63 of contact 53 at 64 are links 65 bearing pivots 66 which are equidistantly spaced from the pivot 64 with pivots 51. Bell crank levers 61 are pivoted to links 85 upon the pivots 66 and are further pivoted to arms 68, aflixed to the blade elements 66, by pivots 88 which, when the blade 55 is in closed position. substantially axially align with the pivots 64. An angular arm 18 on one of these levers is connected to the arm 62 of shaft 68 by link II.

In this form of the invention I have illustrated the operating mechanism as a form which is obviously readily adaptable to the forms of the invention previously described and is commonly I employed in gang switches.

Assuming the parts to be in the position shown in Fig. 14, a pull upon link 16 cannot at this time move the blade 55 because of misalignment of the pivots 5i and 66. This initial movement, therefore, results in a mere pivotal movement of links 85 and levers 61 about their pivots 64 and 59 until these parts reach the dotted line position of said figure, at which time oscillation of the bell crank lever about the pivots 69 has rotated shaft 60 and through the toggles released the clamping engagement of the blade elements 56 with the contact members 54. Blade 55 then starts its rotation about pivots 51, finally reaching the position shown in Fig. 17. It will be noted that in this position there is a positive lock aflorded by the positions of bell crank levers 61 and links 65 preventing any possible movement of the bell crank levers about their pivots 69 until the blade 55 has again returned to its closed position so that the clamping mechanisms are locked in their inoperative positions until the switch closed" position is attained. Attention is further directed to the fact that owing to misalignment of the pivots when the clamping devices are in their clamping position, the switch blade itself is locked in its closed position. Considering, for example, the structure of Fig. 8, if an attempt is made to open the switch without moving the clamping elements to their open position, the link 49 will exert a downward strain on the link 45. This will tend to move the pivot 45 toward the any rotatable member swinging about the pivotal axis of the blade may replace the corresponding clamping arm in the illustrated constructions.

Since the constructions illustrated are, obviously, capable of considerable modification without any departure from the spirit of my invention, I do not wish to be understood as limiting myself thereto except as hereinafter claimed.

I claim:

1. In a switch, spaced stationary contacts, a blade pivoted to one thereof for engagement with the other thereof, a clamping device for the last-named contact carried by said blade for clamping said blade and contact to one another, a movable member carried by the blade and connected with said clampingdevice for actuating said device to open and close the same, and means to positively lock said member against movement when the blade is not in fully closed position, including a link pivoted to a stationary support adjacent the contact to which the blade is pivoted, an operative pivotal connection between said link and movable member, the lastnamed pivot being movable by the clamp actuating movement of the movable member into and out of axial alignment with the pivot of the blade, movement of said movable member to close the clamp moving said last-named pivot out of axial alignment with the pivot of the blade.

2. A switch as claimed in claim 1! wherein the link is directly pivoted to the movable member.

3. A switch as claimed in claim 1 wherein the pivotal connection between the link and movable member comprises a lever pivoted to the blade, the pivotal connection of the link to the support and that of the leverto'the blade being substantially in axial alignment when the blade is in its closed position.

.4. A switch as claimed in claim 1 wherein the pivotal connection between the link and movable member comprises a lever pivoted to the blade, the pivotal connection of the link to the support and that of the lever to the blade being substantially in axial alignment when the blade is in its closed position, the movable member comprising a link shiftable longitudinally. of the blade and a further link connecting said lever andthe movable member.

5. A switch as claimed in claim 1 wherein the pivotal connection between the link and movable member comprises a lever pivoted to the blade, the pivotal connection of the link to the support and that of the lever to'the blade being substantially in axial alignment when the blade is in its closed position, the movable member comprising a shaft rotatably supported by the blade, said shaft having an arm and a further link connecting the arm of the shaft and said lever.

6. In a switch, a stationary contact, a blade, a pivot connecting the blade and contact, a link pivoted to a fixed support at one end and having at its other end a second pivot movable into and out of axial alignment with the blade pivot, a second stationary contact for engagement with said blade, means to clamp said blade to said second contact including a rotatable clamping part, means to simultaneously rotate said rotatable clamping part about its pivot and to swing said link about its pivot on the fixed support, said second pivot of the link movingv into axial alignment with the blade pivot as the rotatable clamping part is moved to released position, and a connection between the link and blade restraining rotation of the blade until said second pivot is axially aligned with the blade pivot.

'7. In a switch, a stationary contact, a blade, a clamping pivot connecting the blade and contact and including a rotatable part coaxial with the blade pivot, a link pivoted to a fixed support at one end and having at its other end a second pivot movable into and out of axial alignment with the blade pivot, a second stationary contact for engagement with said blade, means carried by the blade to clampsaid blade to said second contact including a rotatable clamping part, means carried by the blade to simultaneously rotate said rotatable clamping part about its pivot and to swing said link about its pivot on the fixed support, said second pivot of the link moving into axial alignment with the blade pivot as the rotatable clamping parts are moved to released positions, and a connection between the link and blade restraining rotation of the blade until said second pivot is axially aligned with the blade pivot.

8. A device as claimed in claim I wherein an operating means for said clamping parts and link comprises a rigid link connecting the clamping part and a member rotatable about the blade pivot and with which the second pivot 01 the first-named link is directly engaged.

9. A device as claimed in claim 7 wherein the rigid link connects the rotatable clamping parts and the restraining means comprises a lever engaged with the second pivot oi the first-named link and pivoted to the blade and'a third link connecting said lever and the second-named link.

10. In a switch, spaced stationary contacts, a blade pivoted to one thereof for engagement with the other thereof,v a clamping device for each contact carried by said blade for clamping said blade and contact to 0. ne another, said contacts each comprising a rotatable clamping element, one of said clamping devices likewise constituting the pivot for the blade, the rqtatableclamping; element oi the last-named clamp being rotg tabie about the axis of rotation oi the: blade; aglink connecting said rotatable clamping elements and a second link pivoted at one end to astationary support and at its opposite end to the first-named link, said second link having its pivot axes spaced apart a distance equal to the radial distance between the pivotal axis oi the blade and the axis of the pivotal connection between the associated Pa mer: J. O'BRIEN. 

